Water cycle and rivers

Diagram of the water cycle.

The water cycle has no starting point but we will begin at the ocean

• sun heats water in oceans
• some evaporates as vapour into air
• rising air curents takes vapour into atmosphere
• vapour rises into air where it cools which causes it to condence into clouds
• air currents move clouds around globe which cause them to collide and grow
• Precipitation (rain) then falls from the sky it can also fall as snow
• most precipitation falls back into oceans or over land
• precipitation flow over ground as surface runoff
• bits of runoff enter rivers in vallys
• runoff and ground-water accumulateand are stored as fresh water in lakes
• much of runoff soaks into ground as infiltration
• some ground water finds openings in the land surface and emerges as freshwater springs